:root {
    --primary: #2563EB;
    --primary-dark: #1D4ED8;
    --primary-deep: #1E3A8A;
    --accent: #F59E0B;
    --accent-dark: #D97706;
    --bg: #F1F5F9;
    --surface: #FFFFFF;
    --text: #0F172A;
    --muted: #64748B;
    --border: #E2E8F0;
    --gold: #D97706;
    --silver: #64748B;
    --bronze: #B45309;
    --success: #22C55E;
    --radius: 14px;
    --shadow: 0 18px 40px rgba(29, 78, 216, 0.12);
    --font: 'Poppins', system-ui, sans-serif;
    --max: 1120px;
}

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: var(--font);
    color: var(--text);
    background: var(--bg);
    line-height: 1.55;
    min-height: 100vh;
}

img { max-width: 100%; display: block; }

a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.page-bg {
    position: fixed;
    inset: 0;
    z-index: -1;
    background:
        radial-gradient(ellipse 80% 50% at 10% -10%, rgba(37, 99, 235, 0.22), transparent 55%),
        radial-gradient(ellipse 60% 40% at 100% 0%, rgba(245, 158, 11, 0.16), transparent 50%),
        linear-gradient(180deg, #E8F0FE 0%, #F1F5F9 38%, #F8FAFC 100%);
}

.page-bg::after {
    content: '';
    position: absolute;
    inset: 0;
    opacity: 0.045;
    background-image:
        repeating-linear-gradient(0deg, transparent, transparent 31px, #1D4ED8 32px),
        repeating-linear-gradient(90deg, transparent, transparent 31px, #1D4ED8 32px);
    pointer-events: none;
}

.container {
    width: min(100% - 2rem, var(--max));
    margin-inline: auto;
}

/* Header */
.site-header {
    position: sticky;
    top: 0;
    z-index: 40;
    backdrop-filter: blur(12px);
    background: rgba(248, 250, 252, 0.86);
    border-bottom: 1px solid rgba(226, 232, 240, 0.8);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    min-height: 4.75rem;
}

.header-inner .site-nav {
    margin-left: auto;
    margin-right: 0.5rem;
}

.brand {
    display: inline-flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    flex-shrink: 0;
}

.brand-icon {
    width: 56px;
    height: 56px;
    border-radius: 14px;
}

.brand-wordmark {
    font-weight: 800;
    font-size: 1.7rem;
    letter-spacing: -0.02em;
    line-height: 1;
}

.site-header .brand-wordmark {
    font-size: 1.7rem;
}

.brand-math { color: var(--primary-deep); }
.brand-digits { color: var(--accent); }
.site-footer .brand-math { color: #E0E7FF; }
.site-footer .brand-digits { color: var(--accent); }
.site-footer .brand-wordmark { font-size: 1.35rem; }

.site-nav {
    display: flex;
    align-items: center;
    flex-wrap: nowrap;
    gap: 0.85rem;
}

.site-nav a {
    color: var(--muted);
    font-weight: 500;
    font-size: 0.88rem;
    text-decoration: none;
    white-space: nowrap;
}

.site-nav a:hover,
.site-nav a.is-active {
    color: var(--primary-dark);
}

.header-download {
    flex-shrink: 0;
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.7rem 1.15rem;
    font-size: 0.92rem;
    font-weight: 700;
    white-space: nowrap;
    border-radius: 999px;
    z-index: 2;
}

.header-download-icon {
    font-size: 1.05rem;
    line-height: 1;
}

.btn-download {
    background: #2563EB;
    color: #fff !important;
    box-shadow: 0 8px 22px rgba(37, 99, 235, 0.35);
}

.btn-download:hover {
    background: #1D4ED8;
    color: #fff !important;
    transform: translateY(-1px);
    box-shadow: 0 12px 28px rgba(37, 99, 235, 0.4);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: 0;
    padding: 0.4rem;
    cursor: pointer;
}

.nav-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--primary-dark);
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.4rem;
    padding: 0.85rem 1.4rem;
    border-radius: 999px;
    font-weight: 600;
    font-size: 0.95rem;
    border: 0;
    cursor: pointer;
    text-decoration: none !important;
    transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover { transform: translateY(-1px); }

.btn-primary {
    background: var(--primary);
    color: #fff;
    box-shadow: 0 10px 24px rgba(37, 99, 235, 0.28);
}

.btn-primary:hover { background: var(--primary-dark); color: #fff; }

.btn-accent {
    background: var(--accent);
    color: #1F2937;
    box-shadow: 0 10px 24px rgba(245, 158, 11, 0.28);
}

.btn-accent:hover { background: var(--accent-dark); color: #fff; }

.btn-ghost {
    background: rgba(255, 255, 255, 0.14);
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.35);
}

.btn-ghost:hover { background: rgba(255, 255, 255, 0.24); color: #fff; }

.btn-sm {
    padding: 0.55rem 1rem;
    font-size: 0.85rem;
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 1.5px solid var(--primary);
}

/* Hero */
.hero {
    position: relative;
    min-height: calc(100vh - 4.25rem);
    display: grid;
    align-items: end;
    overflow: hidden;
    color: #fff;
    background:
        linear-gradient(125deg, rgba(30, 58, 138, 0.55) 0%, rgba(29, 78, 216, 0.35) 45%, rgba(15, 23, 42, 0.55) 100%),
        radial-gradient(circle at 70% 30%, rgba(245, 158, 11, 0.25), transparent 40%),
        linear-gradient(160deg, #1D4ED8 0%, #1E3A8A 55%, #0F172A 100%);
}

.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle at 15% 80%, rgba(255,255,255,0.08) 0 2px, transparent 3px),
        radial-gradient(circle at 80% 20%, rgba(255,255,255,0.1) 0 1.5px, transparent 3px),
        radial-gradient(circle at 40% 30%, rgba(245,158,11,0.2) 0 80px, transparent 120px);
    animation: floatGlow 12s ease-in-out infinite alternate;
    pointer-events: none;
}

.hero-inner {
    position: relative;
    padding: 5rem 0 4.5rem;
    max-width: 40rem;
}

.hero-brand {
    font-size: clamp(2.8rem, 8vw, 4.5rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    line-height: 1;
    margin: 0 0 1.25rem;
    animation: riseIn 0.8s ease both;
}

.hero-brand .brand-math { color: #fff; }
.hero-brand .brand-digits { color: var(--accent); }

.hero h1 {
    font-size: clamp(1.5rem, 3.5vw, 2.1rem);
    font-weight: 600;
    margin: 0 0 0.75rem;
    line-height: 1.25;
    animation: riseIn 0.9s 0.1s ease both;
}

.hero-lead {
    margin: 0 0 1.75rem;
    font-size: 1.05rem;
    color: rgba(255, 255, 255, 0.88);
    max-width: 32rem;
    animation: riseIn 1s 0.18s ease both;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    animation: riseIn 1.05s 0.25s ease both;
}

.hero-visual {
    position: absolute;
    right: -4%;
    bottom: 8%;
    width: min(42vw, 420px);
    aspect-ratio: 1;
    border-radius: 50%;
    background:
        radial-gradient(circle at 35% 35%, rgba(245,158,11,0.45), transparent 45%),
        radial-gradient(circle at 65% 60%, rgba(255,255,255,0.15), transparent 50%),
        rgba(255,255,255,0.06);
    display: grid;
    place-items: center;
    animation: pulseSoft 5s ease-in-out infinite;
    pointer-events: none;
}

.hero-visual span {
    font-size: clamp(4rem, 10vw, 7rem);
    font-weight: 800;
    letter-spacing: -0.04em;
    opacity: 0.9;
}

.hero-visual .op {
    position: absolute;
    font-size: 2rem;
    font-weight: 700;
    opacity: 0.55;
}

.hero-visual .op-1 { top: 18%; left: 18%; animation: drift 7s ease-in-out infinite; }
.hero-visual .op-2 { top: 22%; right: 20%; color: var(--accent); animation: drift 8s 0.5s ease-in-out infinite reverse; }
.hero-visual .op-3 { bottom: 24%; left: 22%; animation: drift 6.5s 0.2s ease-in-out infinite; }
.hero-visual .op-4 { bottom: 20%; right: 18%; color: var(--accent); animation: drift 7.5s 0.8s ease-in-out infinite reverse; }

@keyframes riseIn {
    from { opacity: 0; transform: translateY(18px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes pulseSoft {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.04); }
}

@keyframes drift {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
}

@keyframes floatGlow {
    from { opacity: 0.7; transform: translateY(0); }
    to { opacity: 1; transform: translateY(-12px); }
}

/* Sections */
.section {
    padding: 4.5rem 0;
}

.section-head {
    margin-bottom: 1.75rem;
}

.section-head h2 {
    margin: 0 0 0.4rem;
    font-size: clamp(1.6rem, 3vw, 2rem);
    letter-spacing: -0.02em;
}

.section-head p {
    margin: 0;
    color: var(--muted);
    max-width: 36rem;
}

.section-alt {
    background: rgba(255, 255, 255, 0.55);
}

.section-cta {
    background: linear-gradient(120deg, var(--primary-dark), var(--primary-deep));
    color: #fff;
    text-align: center;
}

.section-cta h2 { margin: 0 0 0.5rem; }
.section-cta p { margin: 0 0 1.25rem; color: rgba(255,255,255,0.85); }

.section-actions {
    display: flex;
    justify-content: space-between;
    align-items: end;
    gap: 1rem;
    flex-wrap: wrap;
    margin-bottom: 1.25rem;
}

.link-more {
    font-weight: 600;
    color: var(--primary);
}

/* Leaderboard */
.lb-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1.25rem;
}

.lb-tab {
    padding: 0.55rem 0.95rem;
    border-radius: 999px;
    background: rgba(255,255,255,0.8);
    border: 1px solid var(--border);
    color: var(--muted);
    font-weight: 600;
    font-size: 0.88rem;
    text-decoration: none !important;
}

.lb-tab:hover { color: var(--primary); border-color: #BFDBFE; }

.lb-tab.is-active {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}

.lb-meta {
    color: var(--muted);
    font-size: 0.9rem;
    margin: 0 0 1rem;
}

.lb-board {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
}

.lb-row {
    display: grid;
    grid-template-columns: 3.25rem minmax(0, 1fr) auto;
    gap: 0.85rem;
    align-items: center;
    padding: 0.85rem 1.1rem;
    border-bottom: 1px solid var(--border);
}

.lb-row:last-child { border-bottom: 0; }

.lb-row:nth-child(even) { background: #F8FAFC; }

.lb-rank {
    font-weight: 800;
    font-size: 1.05rem;
    text-align: center;
    color: var(--muted);
}

.lb-rank.gold { color: var(--gold); }
.lb-rank.silver { color: var(--silver); }
.lb-rank.bronze { color: var(--bronze); }

.lb-player {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    min-width: 0;
}

.lb-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
    background: #DBEAFE;
    flex-shrink: 0;
}

.lb-avatar-fallback {
    display: grid;
    place-items: center;
    font-weight: 700;
    color: var(--primary-dark);
    font-size: 0.9rem;
}

.lb-name {
    font-weight: 600;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.lb-score {
    font-weight: 700;
    color: var(--primary-dark);
    white-space: nowrap;
}

.lb-score small {
    display: block;
    font-weight: 500;
    color: var(--muted);
    font-size: 0.7rem;
    text-align: right;
}

.lb-empty,
.lb-error {
    padding: 2.5rem 1.25rem;
    text-align: center;
    color: var(--muted);
    background: var(--surface);
    border: 1px dashed var(--border);
    border-radius: var(--radius);
}

.lb-winners {
    margin-bottom: 1.5rem;
}

.lb-winners h3 {
    margin: 0 0 0.75rem;
    font-size: 1.05rem;
}

/* Games grid */
.games-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1rem;
}

.game-tile {
    position: relative;
    padding: 1.25rem;
    border-radius: var(--radius);
    background: var(--surface);
    border: 1px solid var(--border);
    overflow: hidden;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.game-tile:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}

.game-tile::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 5px;
    background: var(--mode-color, var(--primary));
}

.game-sign {
    font-size: 1.75rem;
    font-weight: 800;
    color: var(--mode-color, var(--primary));
    line-height: 1;
    margin-bottom: 0.5rem;
}

.game-tile h3 {
    margin: 0 0 0.35rem;
    font-size: 1.05rem;
}

.game-tile p {
    margin: 0;
    color: var(--muted);
    font-size: 0.88rem;
}

.feature-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 1rem;
}

.feature-item {
    padding: 1.15rem 0;
    border-top: 1px solid var(--border);
}

.feature-item h3 {
    margin: 0 0 0.35rem;
    font-size: 1.05rem;
}

.feature-item p {
    margin: 0;
    color: var(--muted);
    font-size: 0.92rem;
}

/* Page hero (inner pages) */
.page-hero {
    padding: 3.5rem 0 2rem;
    background: linear-gradient(135deg, rgba(29, 78, 216, 0.1), rgba(245, 158, 11, 0.08));
    border-bottom: 1px solid var(--border);
}

.page-hero h1 {
    margin: 0 0 0.5rem;
    font-size: clamp(1.8rem, 4vw, 2.4rem);
    letter-spacing: -0.02em;
}

.page-hero p {
    margin: 0;
    color: var(--muted);
    max-width: 40rem;
}

.prose {
    max-width: 44rem;
}

.prose h2 {
    margin-top: 2rem;
    font-size: 1.25rem;
}

.prose p, .prose li {
    color: #334155;
}

/* Footer */
.site-footer {
    background: #0F172A;
    color: #CBD5E1;
    padding: 3rem 0 1.5rem;
    margin-top: 2rem;
}

.footer-inner {
    display: grid;
    grid-template-columns: 1.4fr 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-brand p {
    margin: 0.75rem 0 0;
    color: #94A3B8;
    font-size: 0.92rem;
    max-width: 20rem;
}

.footer-links {
    display: flex;
    flex-direction: column;
    gap: 0.55rem;
}

.footer-links a,
.footer-email {
    color: #E2E8F0;
    text-decoration: none;
    font-size: 0.92rem;
}

.footer-links a:hover,
.footer-email:hover { color: var(--accent); }

.footer-cta {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.85rem;
}

.footer-copy {
    border-top: 1px solid rgba(148, 163, 184, 0.2);
    padding-top: 1.25rem;
}

.footer-copy p {
    margin: 0;
    font-size: 0.85rem;
    color: #64748B;
}

@media (max-width: 860px) {
    .nav-toggle { display: flex; order: 3; }

    .header-inner {
        flex-wrap: nowrap;
        gap: 0.5rem;
    }

    .brand { order: 1; }
    .header-download { order: 2; margin-left: auto; }

    .site-nav {
        display: none;
        order: 4;
        position: absolute;
        top: 4.75rem;
        left: 0;
        right: 0;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        margin: 0;
        background: #fff;
        border-bottom: 1px solid var(--border);
        padding: 0.5rem 1rem 1rem;
        box-shadow: 0 12px 30px rgba(15, 23, 42, 0.08);
    }

    .site-nav.is-open { display: flex; }

    .site-nav a {
        padding: 0.75rem 0.25rem;
        border-bottom: 1px solid var(--border);
    }

    .header-download {
        padding: 0.6rem 0.9rem;
        font-size: 0.82rem;
    }

    .hero-visual { opacity: 0.35; width: 55vw; }

    .footer-inner {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}

@media (max-width: 420px) {
    .brand-wordmark { font-size: 1.35rem; }
    .brand-icon { width: 44px; height: 44px; }
    .header-download { padding: 0.55rem 0.75rem; font-size: 0.78rem; }
}

@media (max-width: 560px) {
    .hero-inner { padding: 3.5rem 0 3rem; }
    .lb-row { grid-template-columns: 2.5rem minmax(0, 1fr) auto; padding: 0.75rem; }
}

/* Playable games */
.game-tile-link {
    display: block;
    color: inherit;
    text-decoration: none !important;
    cursor: pointer;
}

.game-tile-link:hover .play-chip {
    background: var(--mode-color, var(--primary));
    color: #fff;
}

.game-tile-link.is-current {
    outline: 2px solid var(--mode-color, var(--primary));
}

.play-chip {
    display: inline-block;
    margin-top: 0.75rem;
    padding: 0.25rem 0.7rem;
    border-radius: 999px;
    font-size: 0.75rem;
    font-weight: 700;
    background: rgba(37, 99, 235, 0.1);
    color: var(--mode-color, var(--primary));
}

.play-back {
    display: inline-block;
    margin-bottom: 0.75rem;
    font-weight: 600;
    color: var(--primary);
    text-decoration: none;
}

.play-section { padding-top: 1.5rem; }

.play-shell {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 18px;
    box-shadow: var(--shadow);
    overflow: hidden;
    max-width: 720px;
    margin: 0 auto;
}

.play-hud {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.5rem;
    padding: 0.9rem 1.1rem;
    background: linear-gradient(120deg, var(--mode-color, var(--primary)), var(--primary-dark));
    color: #fff;
    text-align: center;
}

.hud-label {
    display: block;
    font-size: 0.7rem;
    opacity: 0.85;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.play-hud strong { font-size: 1.15rem; }

.play-stage {
    min-height: 360px;
    padding: 1.5rem 1.25rem 1.75rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 0.85rem;
}

.play-intro { text-align: center; max-width: 28rem; }

.play-intro-sign {
    font-size: 3rem;
    font-weight: 800;
    color: var(--mode-color, var(--primary));
    margin-bottom: 0.5rem;
}

.play-prompt {
    font-size: clamp(2rem, 6vw, 3rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    text-align: center;
    color: var(--text);
}

.play-hint {
    margin: 0;
    color: var(--muted);
    font-weight: 500;
    text-align: center;
}

.play-feedback {
    text-align: center;
    padding: 0.65rem;
    font-weight: 700;
}

.play-feedback.is-ok { background: #DCFCE7; color: #166534; }
.play-feedback.is-bad { background: #FEE2E2; color: #991B1B; }

.choice-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
    width: min(100%, 420px);
}

.choice-btn {
    border: 1.5px solid var(--border);
    background: #F8FAFC;
    border-radius: 12px;
    padding: 1rem 0.75rem;
    font-family: inherit;
    font-size: 1.2rem;
    font-weight: 700;
    cursor: pointer;
    color: var(--text);
    transition: transform 0.15s ease, border-color 0.15s ease, background 0.15s ease;
}

.choice-btn:hover {
    border-color: var(--mode-color, var(--primary));
    background: #EFF6FF;
    transform: translateY(-1px);
}

.keypad { width: min(100%, 280px); }
.keypad-display {
    background: #0F172A;
    color: #fff;
    border-radius: 12px;
    padding: 0.9rem;
    font-size: 1.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 0.65rem;
    min-height: 3.2rem;
}
.keypad-display.is-placeholder { color: #64748B; }
.keypad-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.45rem;
}
.keypad-wide { grid-template-columns: repeat(3, 1fr); }
.keypad-key {
    border: 0;
    background: #E2E8F0;
    border-radius: 10px;
    padding: 0.85rem 0;
    font-family: inherit;
    font-size: 1.1rem;
    font-weight: 700;
    cursor: pointer;
}
.keypad-key.is-ok {
    background: var(--mode-color, var(--primary));
    color: #fff;
    grid-column: span 1;
}

.pattern-grid {
    display: grid;
    gap: 0.5rem;
    width: min(100%, 320px);
}
.pattern-cell {
    aspect-ratio: 1;
    border: 0;
    border-radius: 10px;
    cursor: pointer;
    box-shadow: inset 0 0 0 2px rgba(15,23,42,0.08);
}

.seq-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    margin-bottom: 0.5rem;
}
.seq-item {
    min-width: 3rem;
    padding: 0.75rem 0.9rem;
    background: #EFF6FF;
    border-radius: 10px;
    font-weight: 800;
    font-size: 1.2rem;
    text-align: center;
}
.seq-item.is-missing {
    background: var(--accent);
    color: #1F2937;
}

.timer-bar {
    width: min(100%, 420px);
    height: 6px;
    background: #E2E8F0;
    border-radius: 999px;
    overflow: hidden;
}
.timer-fill {
    height: 100%;
    width: 100%;
    background: var(--mode-color, var(--primary));
}

.compare-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
    width: min(100%, 420px);
}
.compare-num { font-size: 1.5rem !important; }

.symbol-pad {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.5rem;
    width: min(100%, 360px);
}
.replay-row {
    min-height: 2rem;
    font-size: 1.5rem;
    font-weight: 800;
    letter-spacing: 0.15em;
}

.tap-board {
    position: relative;
    width: min(100%, 420px);
    height: 280px;
    background: #F1F5F9;
    border-radius: 14px;
    border: 1px dashed var(--border);
}
.tap-btn {
    position: absolute;
    width: 52px;
    height: 52px;
    border-radius: 50%;
    border: 0;
    background: var(--mode-color, var(--primary));
    color: #fff;
    font-family: inherit;
    font-weight: 800;
    font-size: 1.1rem;
    cursor: pointer;
    box-shadow: 0 6px 14px rgba(37, 99, 235, 0.25);
}
.tap-btn.is-done {
    background: #94A3B8;
    box-shadow: none;
}

.rotate-row {
    display: flex;
    gap: 2rem;
    align-items: center;
    justify-content: center;
    margin: 0.5rem 0 1rem;
}
.rotate-glyph {
    width: 96px;
    height: 96px;
    display: grid;
    place-items: center;
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--mode-color, var(--primary));
    background: #EFF6FF;
    border-radius: 16px;
}

.focus-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 0.35rem;
    width: min(100%, 360px);
}
.focus-cell {
    aspect-ratio: 1;
    border: 0;
    border-radius: 8px;
    background: #E2E8F0;
    font-family: inherit;
    font-weight: 700;
    font-size: 0.95rem;
    cursor: pointer;
}
.focus-cell.is-cleared {
    background: #BBF7D0;
    color: #166534;
}

.brain-more {
    margin-top: 2.5rem;
}
.brain-more h3 {
    margin: 0 0 1rem;
    font-size: 1.15rem;
}
.brain-grid-sm .game-tile {
    padding: 1rem;
}
.brain-grid-sm .game-tile h3 {
    font-size: 0.95rem;
    margin: 0;
}
.brain-grid-sm .game-sign {
    font-size: 1.25rem;
    margin-bottom: 0.35rem;
}

.section-cta .btn-ghost {
    border-color: rgba(255,255,255,0.45);
}

@media (max-width: 560px) {
    .play-stage { min-height: 320px; padding: 1.1rem; }
    .tap-board { height: 240px; }
}

/* ?? Marketing expansion ?? */
.stats-section { padding: 2rem 0; }
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 1.5rem 1rem;
    box-shadow: var(--shadow);
    text-align: center;
}
.stat-item strong {
    display: block;
    font-size: clamp(1.4rem, 3vw, 2rem);
    color: var(--primary-dark);
    letter-spacing: -0.02em;
}
.stat-item span {
    color: var(--muted);
    font-size: 0.85rem;
    font-weight: 500;
}

.home-spotlight {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
}
.spotlight-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.35rem;
    box-shadow: 0 10px 28px rgba(15, 23, 42, 0.06);
}
.spotlight-kicker {
    margin: 0 0 0.5rem;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--accent-dark);
}
.spotlight-card h3 { margin: 0 0 0.5rem; font-size: 1.2rem; }
.spotlight-card p { margin: 0 0 0.85rem; color: var(--muted); font-size: 0.92rem; }
.champion-row {
    display: flex;
    gap: 0.85rem;
    align-items: center;
    margin-bottom: 0.75rem;
}
.champion-row h3 { margin: 0; }
.champion-row p { margin: 0.15rem 0 0; }
.muted-line { color: var(--muted); font-size: 0.9rem; }

.countdown {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.4rem;
    margin: 0.75rem 0 1rem;
    text-align: center;
}
.countdown div {
    background: #EFF6FF;
    border-radius: 10px;
    padding: 0.55rem 0.25rem;
}
.countdown strong {
    display: block;
    font-size: 1.25rem;
    color: var(--primary-dark);
}
.countdown span {
    font-size: 0.65rem;
    text-transform: uppercase;
    color: var(--muted);
    font-weight: 600;
}
.countdown-lg strong { font-size: 1.6rem; }

.hof-teaser { padding-top: 1rem; }
.hof-banner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1.5rem;
    padding: 2rem;
    border-radius: 20px;
    background: linear-gradient(125deg, #1E3A8A, #2563EB 55%, #D97706);
    color: #fff;
    box-shadow: var(--shadow);
}
.hof-banner h2 { margin: 0 0 0.35rem; font-size: clamp(1.5rem, 3vw, 2rem); }
.hof-banner .spotlight-kicker { color: var(--accent); }
.hof-name { margin: 0; font-size: 1.5rem; font-weight: 800; }
.hof-meta { margin: 0.25rem 0 1rem; opacity: 0.9; }
.hof-avatar, .hof-avatar-lg {
    border-radius: 50%;
    border: 4px solid rgba(255,255,255,0.5);
    object-fit: cover;
    background: #DBEAFE;
}
.hof-avatar-lg { width: 96px; height: 96px; margin: 0.5rem auto 0.75rem; display: block; }

.hof-hero { background: linear-gradient(135deg, rgba(29,78,216,0.16), rgba(245,158,11,0.12)); }
.hof-feature {
    display: grid;
    grid-template-columns: 0.9fr 1.4fr;
    gap: 1.5rem;
    align-items: start;
}
.hof-crown-card {
    text-align: center;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 1.75rem 1.25rem;
    box-shadow: var(--shadow);
}
.hof-crown-card h2 { margin: 0.25rem 0; font-size: 1.6rem; }
.hof-country { color: var(--muted); margin: 0 0 1rem; }
.hof-score-box {
    display: inline-flex;
    flex-direction: column;
    background: #FFFBEB;
    border: 1px solid #FDE68A;
    border-radius: 12px;
    padding: 0.75rem 1.5rem;
}
.hof-score-box span { font-size: 0.75rem; color: var(--muted); font-weight: 600; text-transform: uppercase; }
.hof-score-box strong { font-size: 1.75rem; color: var(--accent-dark); }
.hof-panels {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}
.hof-panels h3 { margin: 0 0 0.75rem; font-size: 1.05rem; }

.champion-strip {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem 1.25rem;
    align-items: baseline;
    margin-bottom: 1rem;
    padding: 0.85rem 1rem;
    background: #EFF6FF;
    border-radius: 12px;
}
.champion-strip strong { font-size: 1.15rem; }

.country-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 0.75rem;
}
.country-card {
    display: grid;
    grid-template-columns: auto auto 1fr;
    gap: 0.65rem;
    align-items: center;
    padding: 0.85rem 1rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
}
.country-card h3 { margin: 0; font-size: 1rem; }
.country-card p { margin: 0.15rem 0 0; color: var(--muted); font-size: 0.82rem; }
.country-rank { font-weight: 800; color: var(--muted); }
.country-rank.gold { color: var(--gold); }
.country-rank.silver { color: var(--silver); }
.country-rank.bronze { color: var(--bronze); }
.country-flag { font-size: 1.5rem; }

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 1rem;
}
.news-grid-lg { grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); }
.news-card {
    display: block;
    padding: 1.25rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    text-decoration: none !important;
    color: inherit;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.news-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}
.news-card time {
    font-size: 0.8rem;
    color: var(--muted);
    font-weight: 600;
}
.news-card h2, .news-card h3 {
    margin: 0.4rem 0;
    font-size: 1.1rem;
    color: var(--text);
}
.news-card p { margin: 0; color: var(--muted); font-size: 0.9rem; }

.article-prose time { color: var(--muted); font-weight: 600; font-size: 0.9rem; }
.article-prose h1 { margin: 0.5rem 0 1rem; }
.article-prose .lead { font-size: 1.05rem; color: var(--muted); }
.article-cta {
    margin-top: 2rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
}
.article-cta .btn { margin-right: 0.5rem; margin-top: 0.5rem; }

.tournament-layout {
    display: grid;
    grid-template-columns: 0.9fr 1.2fr;
    gap: 2rem;
    align-items: start;
}
.prize-box {
    display: flex;
    flex-direction: column;
    background: #FFFBEB;
    border-radius: 12px;
    padding: 0.85rem 1rem;
    margin-bottom: 1rem;
}
.prize-box span { font-size: 0.75rem; text-transform: uppercase; color: var(--muted); font-weight: 700; }
.prize-box strong { font-size: 1.4rem; color: var(--accent-dark); }
.lane-list {
    margin: 0 0 1rem;
    padding-left: 1.1rem;
    color: var(--muted);
}

.coming-soon-panel {
    text-align: center;
    padding: 3rem 1.5rem;
    background: var(--surface);
    border: 1px dashed var(--border);
    border-radius: 16px;
}
.classic-tabs-note {
    margin-top: 2.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border);
}
.classic-tabs-note > p {
    margin: 0 0 0.75rem;
    color: var(--muted);
    font-size: 0.9rem;
}

.shop-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1rem;
}
.shop-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 1.1rem;
    position: relative;
    overflow: hidden;
}
.shop-swatch {
    height: 72px;
    border-radius: 10px;
    margin-bottom: 0.75rem;
    background: linear-gradient(135deg, var(--item-color), #1E3A8A);
}
.shop-card h3 { margin: 0 0 0.5rem; font-size: 1rem; }
.shop-lock {
    font-size: 0.75rem;
    font-weight: 700;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.footer-inner-wide {
    grid-template-columns: 1.3fr 1fr 1fr 1fr;
}
.footer-links strong {
    display: block;
    color: #fff;
    margin-bottom: 0.5rem;
    font-size: 0.85rem;
}
.footer-legal-inline {
    display: flex;
    gap: 0.85rem;
}
.footer-legal-inline a { color: #94A3B8; font-size: 0.85rem; }

.lb-tab small { font-weight: 500; opacity: 0.8; }

@media (max-width: 960px) {
    .stats-grid { grid-template-columns: repeat(2, 1fr); }
    .home-spotlight, .hof-feature, .tournament-layout, .hof-panels {
        grid-template-columns: 1fr;
    }
    .footer-inner-wide { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 560px) {
    .footer-inner-wide { grid-template-columns: 1fr; }
    .hof-banner { flex-direction: column; text-align: center; }
}

/* Worksheets */
.grade-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1rem;
}
.grade-card {
    display: block;
    padding: 1.35rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-left: 5px solid var(--grade-color, var(--primary));
    border-radius: 14px;
    text-decoration: none !important;
    color: inherit;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.grade-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}
.grade-badge {
    display: inline-block;
    font-weight: 800;
    font-size: 1.25rem;
    color: var(--grade-color, var(--primary));
}
.grade-sub { margin: 0.4rem 0; color: var(--muted); font-size: 0.9rem; }
.grade-meta { margin: 0 0 0.75rem; font-size: 0.82rem; font-weight: 600; color: var(--text); }

.ws-category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1rem;
}
.ws-category-card {
    display: block;
    padding: 1.2rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 14px;
    text-decoration: none !important;
    color: inherit;
    position: relative;
    overflow: hidden;
}
.ws-category-card::before {
    content: '';
    position: absolute;
    left: 0; top: 0; bottom: 0;
    width: 4px;
    background: var(--mode-color, var(--primary));
}
.ws-category-card h3 { margin: 0 0 0.25rem; font-size: 1.05rem; }
.ws-category-card p { margin: 0; color: var(--muted); font-size: 0.88rem; }

.ws-crumbs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    align-items: center;
    margin-bottom: 0.75rem;
    font-size: 0.88rem;
    color: var(--muted);
}
.ws-crumbs a { color: var(--primary); font-weight: 600; text-decoration: none; }

.ws-list { display: flex; flex-direction: column; gap: 0.75rem; }
.ws-list-item {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    align-items: center;
    padding: 1.1rem 1.25rem;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    text-decoration: none !important;
    color: inherit;
}
.ws-list-item:hover { border-color: #BFDBFE; box-shadow: var(--shadow); }
.ws-list-item h3 { margin: 0 0 0.25rem; font-size: 1.05rem; }
.ws-list-item p { margin: 0; color: var(--muted); font-size: 0.88rem; }
.ws-list-meta {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 0.35rem;
    white-space: nowrap;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--muted);
}

.ws-actions { display: flex; flex-wrap: wrap; gap: 0.65rem; margin-top: 1rem; }

.worksheet-sheet { padding-top: 1rem; }
.sheet-header {
    display: flex;
    justify-content: space-between;
    gap: 1.5rem;
    flex-wrap: wrap;
    padding-bottom: 1rem;
    margin-bottom: 1.25rem;
    border-bottom: 2px solid var(--border);
}
.sheet-brand { margin: 0; font-weight: 800; font-size: 0.95rem; }
.sheet-header h2 { margin: 0.25rem 0; font-size: 1.5rem; }
.sheet-header p { margin: 0; color: var(--muted); font-size: 0.9rem; }
.sheet-student p { margin: 0.35rem 0; font-weight: 500; }

.sheet-problems {
    list-style: none;
    margin: 0;
    padding: 0;
    counter-reset: q;
}
.sheet-problems.is-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.85rem 1.5rem;
}
.sheet-problems.is-wide {
    display: flex;
    flex-direction: column;
    gap: 1.1rem;
}
.sheet-problems li {
    counter-increment: q;
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    gap: 0.35rem 0.5rem;
    padding: 0.55rem 0;
    border-bottom: 1px dashed #E2E8F0;
    font-size: 1.05rem;
    font-weight: 600;
}
.sheet-problems li::before {
    content: counter(q) ".";
    color: var(--muted);
    font-weight: 700;
    min-width: 1.5rem;
}
.sheet-blank { letter-spacing: 0.08em; color: var(--muted); font-weight: 500; }
.sheet-line { display: block; width: 100%; margin-top: 0.35rem; color: var(--muted); font-weight: 400; }
.sheet-answer {
    width: 100%;
    font-size: 0.85rem;
    color: #166534;
    font-weight: 700;
}
.sheet-footer { margin-top: 2rem; color: var(--muted); font-size: 0.9rem; }

@media (max-width: 640px) {
    .sheet-problems.is-grid { grid-template-columns: 1fr; }
    .ws-list-item { flex-direction: column; align-items: flex-start; }
    .ws-list-meta { align-items: flex-start; flex-direction: row; }
}

@media print {
    .site-header, .site-footer, .page-bg, .no-print, .page-hero.no-print { display: none !important; }
    body { background: #fff; }
    .worksheet-sheet { padding: 0; }
    .sheet-problems li { break-inside: avoid; }
}

/* Worksheet generator UI */
.ws-group { margin-bottom: 2.25rem; }
.ws-group-title {
    margin: 0 0 0.85rem;
    font-size: 1.15rem;
    color: var(--primary-dark);
}
.ws-generate-panel {
    max-width: 640px;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
}
/* Honeypot ? hidden from humans, bots that autofill get blocked */
.ws-hp {
    position: absolute !important;
    left: -10000px !important;
    top: auto !important;
    width: 1px !important;
    height: 1px !important;
    overflow: hidden !important;
    opacity: 0 !important;
    pointer-events: none !important;
}
.ws-alert-error {
    max-width: 640px;
    margin: 0 0 1rem;
    padding: 0.85rem 1rem;
    border-radius: 12px;
    background: #FEF2F2;
    border: 1px solid #FECACA;
    color: #991B1B;
    font-size: 0.95rem;
}
.ws-turnstile {
    margin: 0 0 1rem;
    min-height: 0;
}
.ws-option-block { margin-bottom: 1.35rem; }
.ws-option-block h2 {
    margin: 0 0 0.65rem;
    font-size: 1rem;
}
.ws-option-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}
.ws-radio {
    cursor: pointer;
}
.ws-radio input { position: absolute; opacity: 0; pointer-events: none; }
.ws-radio span {
    display: inline-block;
    padding: 0.55rem 1rem;
    border-radius: 999px;
    border: 1.5px solid var(--border);
    font-weight: 600;
    font-size: 0.9rem;
    background: #F8FAFC;
}
.ws-radio input:checked + span {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}
.ws-feature-ticks {
    margin: 0;
    padding-left: 1.1rem;
    color: var(--muted);
    font-size: 0.92rem;
}
.ws-feature-ticks li { margin: 0.25rem 0; }
.btn-lg { padding: 0.95rem 1.6rem; font-size: 1.05rem; }
.ws-pill {
    display: inline-block;
    margin: 0 0.35rem 0.35rem 0;
    padding: 0.25rem 0.7rem;
    border-radius: 999px;
    background: #EFF6FF;
    color: var(--primary-dark);
    font-size: 0.8rem;
    font-weight: 700;
}
.sheet-type-tag {
    display: inline-block;
    margin-right: 0.4rem;
    padding: 0.1rem 0.45rem;
    border-radius: 6px;
    background: #F1F5F9;
    color: var(--muted);
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    vertical-align: middle;
}
.sheet-choices {
    width: 100%;
    margin-top: 0.35rem;
    font-weight: 500;
    color: #334155;
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem 1.25rem;
}
.sheet-match {
    width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-top: 0.5rem;
    font-weight: 500;
}
.sheet-q-block { width: 100%; }

.ws-ready-item {
    flex-wrap: wrap;
}
.ws-ready-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    align-items: center;
}

/* Kindergarten colorful worksheets */
.page-hero-kinder {
    background: linear-gradient(135deg, #FEF3C7, #FCE7F3 40%, #DBEAFE) !important;
}
.worksheet-kinder {
    background: linear-gradient(180deg, #FFF7ED 0%, #F0FDF4 50%, #EFF6FF 100%);
    border-radius: 20px;
    padding: 1.5rem 0 2rem;
}
.sheet-header-kinder {
    background: linear-gradient(90deg, #FDE68A, #FBCFE8, #BFDBFE);
    border: 0 !important;
    border-radius: 16px;
    padding: 1.1rem 1.25rem !important;
    margin-bottom: 1.5rem !important;
}
.worksheet-kinder .sheet-problems li {
    border: 0 !important;
    border-radius: 18px;
    padding: 1rem 1.1rem 1.15rem !important;
    margin-bottom: 0.85rem;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.06);
}
.worksheet-kinder .sheet-problems li::before {
    background: #fff;
    border-radius: 50%;
    width: 1.75rem;
    height: 1.75rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    color: #1D4ED8;
    box-shadow: 0 2px 6px rgba(0,0,0,0.08);
}
.k-card-1 { background: #FEF3C7; }
.k-card-2 { background: #FCE7F3; }
.k-card-3 { background: #DBEAFE; }
.k-card-4 { background: #DCFCE7; }
.k-card-5 { background: #FFEDD5; }
.k-card-6 { background: #E0E7FF; }

.k-visual-row {
    font-size: 1.85rem;
    line-height: 1.5;
    letter-spacing: 0.12em;
    margin: 0.35rem 0 0.55rem;
    word-break: break-word;
}
.k-big-number {
    font-size: 4.5rem;
    font-weight: 800;
    color: #2563EB;
    text-align: center;
    margin: 0.4rem 0;
    text-shadow: 2px 2px 0 #FDE68A;
}
.k-big-shape {
    font-size: 4rem;
    text-align: center;
    margin: 0.35rem 0;
}
.k-focus-number {
    display: inline-block;
    min-width: 4rem;
    padding: 0.5rem 1rem;
    margin: 0.4rem 0;
    border-radius: 16px;
    background: #2563EB;
    color: #fff;
    font-size: 2.4rem;
    font-weight: 800;
    text-align: center;
}
.k-number-seq {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    margin: 0.5rem 0;
}
.k-num-bubble {
    min-width: 2.6rem;
    height: 2.6rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: #fff;
    border: 3px solid #60A5FA;
    font-weight: 800;
    font-size: 1.2rem;
    color: #1D4ED8;
}
.k-num-bubble.is-missing {
    background: #F59E0B;
    border-color: #D97706;
    color: #fff;
}
.k-add-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.45rem;
    margin: 0.4rem 0;
}
.k-op {
    font-size: 1.6rem;
    font-weight: 800;
    color: #DB2777;
}
.k-sub-note {
    margin: 0.25rem 0 0;
    font-weight: 700;
    color: #B45309;
}
.k-compare {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.65rem;
    margin: 0.5rem 0;
}
.k-compare-box {
    background: rgba(255,255,255,0.75);
    border-radius: 14px;
    padding: 0.65rem;
    border: 2px dashed #94A3B8;
}
.k-compare-label {
    display: inline-block;
    background: #2563EB;
    color: #fff;
    font-weight: 800;
    border-radius: 8px;
    padding: 0.15rem 0.55rem;
    margin-bottom: 0.35rem;
    font-size: 0.85rem;
}
.k-choices {
    display: flex !important;
    flex-wrap: wrap;
    gap: 0.5rem !important;
}
.k-choice {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.45rem 0.85rem;
    border-radius: 999px;
    font-weight: 700;
    font-size: 1.05rem;
    background: #fff;
    border: 2px solid transparent;
}
.k-choice-1 { border-color: #F59E0B; color: #B45309; }
.k-choice-2 { border-color: #EC4899; color: #BE185D; }
.k-choice-3 { border-color: #22C55E; color: #15803D; }
.k-choice-4 { border-color: #3B82F6; color: #1D4ED8; }
.k-choice-ring {
    width: 1rem;
    height: 1rem;
    border-radius: 50%;
    border: 2px solid currentColor;
    display: inline-block;
}
.k-match-cell {
    background: #fff;
    border-radius: 10px;
    padding: 0.45rem 0.6rem;
    margin-bottom: 0.4rem;
    border: 2px solid #F9A8D4;
    font-size: 1.05rem;
}
.k-write-line, .k-write-box {
    display: block;
    margin-top: 0.5rem;
    padding: 0.65rem;
    border: 3px dashed #F59E0B;
    border-radius: 12px;
    background: #FFFBEB;
    color: #92400E;
    font-weight: 700;
    text-align: center;
}
.worksheet-kinder .sheet-q {
    font-size: 1.15rem;
    color: #0F172A;
}
.worksheet-kinder .sheet-answer {
    background: #DCFCE7;
    border-radius: 8px;
    padding: 0.35rem 0.55rem;
    margin-top: 0.45rem;
}

@media print {
    .worksheet-kinder {
        background: #fff !important;
        padding: 0 !important;
    }
    .worksheet-kinder .sheet-problems li {
        box-shadow: none !important;
        border: 2px solid #e2e8f0 !important;
    }
}

/* Formula Library */
.formulas-hero {
    position: relative;
    overflow: hidden;
    background:
        radial-gradient(circle at 15% 20%, color-mix(in srgb, var(--f-color, #2563EB) 22%, transparent), transparent 45%),
        radial-gradient(circle at 90% 10%, color-mix(in srgb, var(--f-accent, #F59E0B) 35%, transparent), transparent 40%),
        linear-gradient(135deg, #EFF6FF, #FFF7ED 55%, #FDF2F8) !important;
}
.formulas-kicker { color: var(--f-color, var(--primary)) !important; }
.formulas-hero-inner { position: relative; }
.formulas-orbit {
    position: absolute;
    right: 0;
    top: 0.5rem;
    width: 180px;
    height: 180px;
    pointer-events: none;
}
.formulas-orbit span {
    position: absolute;
    font-weight: 800;
    font-size: 1.4rem;
    color: var(--primary);
    opacity: 0.35;
    animation: formulaOrbit 8s linear infinite;
}
.formulas-orbit span:nth-child(1) { top: 10%; left: 40%; animation-delay: 0s; color: #2563EB; }
.formulas-orbit span:nth-child(2) { top: 35%; right: 5%; animation-delay: -1.5s; color: #DB2777; }
.formulas-orbit span:nth-child(3) { bottom: 20%; left: 20%; animation-delay: -3s; color: #D97706; }
.formulas-orbit span:nth-child(4) { top: 55%; left: 55%; animation-delay: -4.5s; color: #7C3AED; }
.formulas-orbit span:nth-child(5) { bottom: 5%; right: 30%; animation-delay: -6s; color: #059669; }

@keyframes formulaOrbit {
    0% { transform: translateY(0) rotate(0deg) scale(1); opacity: 0.25; }
    50% { transform: translateY(-12px) rotate(8deg) scale(1.08); opacity: 0.55; }
    100% { transform: translateY(0) rotate(0deg) scale(1); opacity: 0.25; }
}

.formula-cat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
    gap: 1rem;
}
.formula-cat-card {
    display: block;
    padding: 1.35rem 1.25rem;
    border-radius: 18px;
    text-decoration: none !important;
    color: inherit;
    background: linear-gradient(160deg, #fff, color-mix(in srgb, var(--f-accent) 28%, #fff));
    border: 1px solid color-mix(in srgb, var(--f-color) 18%, #E2E8F0);
    box-shadow: 0 14px 30px rgba(15, 23, 42, 0.06);
    transform: translateY(12px);
    opacity: 0;
    animation: formulaRise 0.55s ease forwards;
    animation-delay: var(--delay, 0s);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.formula-cat-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 18px 36px color-mix(in srgb, var(--f-color) 22%, transparent);
}
.formula-cat-icon {
    display: inline-flex;
    width: 3rem;
    height: 3rem;
    align-items: center;
    justify-content: center;
    border-radius: 14px;
    background: var(--f-color);
    color: #fff;
    font-size: 1.35rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
    animation: formulaPop 2.8s ease-in-out infinite;
}
.formula-cat-card h2 {
    margin: 0 0 0.35rem;
    font-size: 1.2rem;
    color: var(--f-color);
}
.formula-cat-card p {
    margin: 0 0 0.85rem;
    color: var(--muted);
    font-size: 0.9rem;
}

@keyframes formulaRise {
    to { opacity: 1; transform: translateY(0); }
}
@keyframes formulaPop {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.06); }
}

.formula-spotlight {
    display: grid;
    grid-template-columns: 1.2fr 0.9fr;
    gap: 1.5rem;
    align-items: center;
}
.formula-preview-card {
    border-radius: 20px;
    padding: 1.4rem;
    background: linear-gradient(145deg, #fff, #FDF2F8);
    border: 2px solid color-mix(in srgb, var(--f-color) 30%, #fff);
    box-shadow: 0 16px 40px rgba(219, 39, 119, 0.12);
    animation: formulaFloat 4s ease-in-out infinite;
}
.formula-preview-label {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--f-color);
    margin-bottom: 0.35rem;
}
.formula-preview-card h3 { margin: 0 0 0.65rem; }
.formula-preview-card ul {
    margin: 0.85rem 0 0;
    padding-left: 1.1rem;
    color: var(--muted);
}
@keyframes formulaFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.formula-chip {
    display: inline-block;
    padding: 0.45rem 0.85rem;
    border-radius: 12px;
    background: color-mix(in srgb, var(--f-color, var(--primary)) 12%, #fff);
    color: var(--f-color, var(--primary-dark));
    font-weight: 800;
    font-size: 1.05rem;
    letter-spacing: 0.01em;
}

.formula-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1rem;
}
.formula-card {
    display: block;
    padding: 1.2rem;
    border-radius: 16px;
    background: #fff;
    border: 1px solid var(--border);
    border-top: 4px solid var(--f-color);
    text-decoration: none !important;
    color: inherit;
    opacity: 0;
    transform: translateY(14px);
    animation: formulaRise 0.5s ease forwards;
    animation-delay: var(--delay, 0s);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.formula-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}
.formula-card-top {
    display: flex;
    flex-direction: column;
    gap: 0.55rem;
    margin-bottom: 0.5rem;
}
.formula-card h2 {
    margin: 0;
    font-size: 1.1rem;
}
.formula-card > p {
    margin: 0 0 0.85rem;
    color: var(--muted);
    font-size: 0.9rem;
}
.formula-example-mini {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.55rem 0.7rem;
    border-radius: 10px;
    background: color-mix(in srgb, var(--f-accent) 35%, #fff);
    font-size: 0.88rem;
}
.formula-example-mini strong { color: var(--f-color); }
.formula-other-cats { margin-top: 2.5rem; }
.formula-other-cats h3 { margin: 0 0 0.75rem; }

.formula-detail {
    display: grid;
    grid-template-columns: 1.4fr 0.8fr;
    gap: 1.5rem;
    align-items: start;
}
.formula-detail-card {
    position: relative;
    overflow: hidden;
    background: #fff;
    border-radius: 22px;
    padding: 1.75rem;
    border: 1px solid var(--border);
    box-shadow: 0 20px 50px rgba(15, 23, 42, 0.08);
}
.formula-detail-glow {
    position: absolute;
    width: 220px;
    height: 220px;
    border-radius: 50%;
    right: -60px;
    top: -60px;
    background: radial-gradient(circle, color-mix(in srgb, var(--f-accent) 70%, transparent), transparent 70%);
    animation: formulaGlow 5s ease-in-out infinite alternate;
    pointer-events: none;
}
@keyframes formulaGlow {
    from { transform: scale(1); opacity: 0.7; }
    to { transform: scale(1.2); opacity: 1; }
}
.formula-detail-label {
    margin: 0 0 0.5rem;
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--f-color);
}
.formula-big {
    font-size: clamp(1.8rem, 4vw, 2.6rem);
    font-weight: 800;
    color: var(--f-color);
    margin-bottom: 0.5rem;
    animation: formulaPulse 2.5s ease-in-out infinite;
}
@keyframes formulaPulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.03); }
}
.formula-pretty {
    margin: 0 0 1.25rem;
    color: var(--muted);
}
.formula-example-box {
    background: linear-gradient(160deg, color-mix(in srgb, var(--f-accent) 40%, #fff), #fff);
    border-radius: 16px;
    padding: 1.15rem 1.25rem;
    border: 1px dashed color-mix(in srgb, var(--f-color) 35%, #E2E8F0);
}
.formula-example-box h2 {
    margin: 0 0 0.65rem;
    font-size: 1.05rem;
    color: var(--f-color);
}
.formula-example-box ul {
    margin: 0 0 1rem;
    padding-left: 1.1rem;
    color: #334155;
}
.formula-example-box li {
    margin: 0.3rem 0;
    animation: formulaRise 0.45s ease both;
}
.formula-example-box li:nth-child(1) { animation-delay: 0.05s; }
.formula-example-box li:nth-child(2) { animation-delay: 0.12s; }
.formula-example-box li:nth-child(3) { animation-delay: 0.19s; }
.formula-example-box li:nth-child(4) { animation-delay: 0.26s; }
.formula-result {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 0.9rem;
    border-radius: 12px;
    background: var(--f-color);
    color: #fff;
}
.formula-result span {
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    opacity: 0.9;
}
.formula-result strong { font-size: 1.25rem; }
.formula-detail-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    margin-top: 1.25rem;
}
.formula-related h3 { margin: 0 0 0.75rem; }
.formula-related-item {
    display: block;
    padding: 0.85rem 1rem;
    margin-bottom: 0.55rem;
    border-radius: 12px;
    background: #fff;
    border: 1px solid var(--border);
    text-decoration: none !important;
    color: inherit;
    transition: transform 0.15s ease, border-color 0.15s ease;
}
.formula-related-item:hover {
    transform: translateX(4px);
    border-color: #BFDBFE;
}
.formula-related-item strong { display: block; margin-bottom: 0.2rem; }
.formula-related-item span { color: var(--muted); font-size: 0.88rem; font-weight: 600; }

@media (max-width: 860px) {
    .formula-spotlight,
    .formula-detail {
        grid-template-columns: 1fr;
    }
    .formulas-orbit { display: none; }
}

/* Fallback when color-mix unsupported */
@supports not (background: color-mix(in srgb, red 50%, blue)) {
    .formula-cat-card { background: #fff; }
    .formula-chip { background: #EFF6FF; color: #1D4ED8; }
    .formula-example-box { background: #FFF7ED; }
}

/* Calculators */
.calc-hero {
    background:
        radial-gradient(circle at 12% 20%, rgba(37,99,235,.16), transparent 42%),
        radial-gradient(circle at 88% 10%, rgba(245,158,11,.22), transparent 40%),
        linear-gradient(135deg, #EFF6FF, #FFF7ED) !important;
}
.calc-cat-block { margin-bottom: 2.25rem; }
.calc-cat-block h2 {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin: 0 0 0.85rem;
    color: var(--c-color, var(--primary));
    font-size: 1.25rem;
}
.calc-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 0.85rem;
}
.calc-card {
    display: block;
    padding: 1.1rem 1.15rem;
    border-radius: 14px;
    background: #fff;
    border: 1px solid var(--border);
    text-decoration: none !important;
    color: inherit;
    transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.calc-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
    border-color: #BFDBFE;
}
.calc-card h3 { margin: 0 0 0.35rem; font-size: 1.02rem; }
.calc-card p { margin: 0 0 0.7rem; color: var(--muted); font-size: 0.88rem; }

.calc-layout {
    display: grid;
    grid-template-columns: 1.35fr 0.85fr;
    gap: 1.5rem;
    align-items: start;
}
.calc-panel {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 1.35rem;
    box-shadow: 0 16px 40px rgba(15,23,42,.06);
}
.calc-form { display: grid; gap: 0.85rem; }
.calc-field { display: grid; gap: 0.35rem; font-weight: 600; font-size: 0.9rem; }
.calc-field input,
.calc-field select,
.calc-field textarea {
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 0.7rem 0.85rem;
    font: inherit;
    background: #F8FAFC;
}
.calc-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}
.calc-hint { margin: 0; color: var(--muted); font-size: 0.85rem; }
.calc-result {
    margin-top: 1.1rem;
    padding: 1rem 1.1rem;
    border-radius: 14px;
    background: linear-gradient(135deg, #2563EB, #1D4ED8);
    color: #fff;
    animation: formulaRise .35s ease;
}
.calc-result-label {
    display: block;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: .06em;
    text-transform: uppercase;
    opacity: .85;
    margin-bottom: 0.25rem;
}
.calc-result strong { font-size: 1.55rem; display: block; }
.calc-result p { margin: 0.35rem 0 0; opacity: .9; font-size: 0.92rem; }
.calc-error {
    margin-top: 0.85rem;
    color: #B91C1C;
    font-weight: 600;
}
.calc-aside {
    background: #FFF7ED;
    border-radius: 16px;
    padding: 1.25rem;
    border: 1px solid #FDE68A;
}
.calc-aside h2 { margin: 0 0 0.5rem; font-size: 1.15rem; }
.calc-aside h3 { margin: 1.25rem 0 0.5rem; font-size: 1rem; }
.calc-aside .btn { margin: 0.35rem 0.35rem 0 0; }
.calc-related { list-style: none; padding: 0; margin: 0; }
.calc-related li { margin: 0.35rem 0; }
.calc-related a { font-weight: 600; color: var(--primary); text-decoration: none; }
.calc-related a:hover { text-decoration: underline; }

.sci-calc { display: grid; gap: 0.75rem; }
.sci-display {
    width: 100%;
    text-align: right;
    font-size: 1.6rem;
    font-weight: 700;
    padding: 0.9rem 1rem;
    border-radius: 12px;
    border: 1px solid var(--border);
    background: #0F172A;
    color: #F8FAFC;
}
.sci-keys {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 0.45rem;
}
.sci-key {
    border: 0;
    border-radius: 10px;
    padding: 0.75rem 0.4rem;
    font: inherit;
    font-weight: 700;
    background: #E2E8F0;
    cursor: pointer;
}
.sci-key:hover { background: #CBD5E1; }
.sci-key[data-k="="] { background: #2563EB; color: #fff; }
.sci-key[data-k="C"] { background: #FCA5A5; }

/* Practice Generator */
.practice-hero {
    background:
        radial-gradient(circle at 20% 30%, color-mix(in srgb, var(--p-color, #22C55E) 22%, transparent), transparent 45%),
        linear-gradient(135deg, #ECFDF5, #EFF6FF) !important;
}
.practice-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
    gap: 1rem;
}
.practice-card {
    display: block;
    padding: 1.25rem;
    border-radius: 16px;
    background: #fff;
    border: 1px solid var(--border);
    border-top: 4px solid var(--p-color);
    text-decoration: none !important;
    color: inherit;
    transition: transform .18s ease, box-shadow .18s ease;
}
.practice-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}
.practice-sign {
    width: 2.75rem;
    height: 2.75rem;
    border-radius: 12px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--p-color);
    color: #fff;
    font-weight: 800;
    font-size: 1.25rem;
    margin-bottom: 0.65rem;
}
.practice-sign-lg {
    width: 4rem;
    height: 4rem;
    font-size: 1.75rem;
    margin-bottom: 0.85rem;
}
.practice-card h2 { margin: 0 0 0.35rem; font-size: 1.1rem; }
.practice-card p { margin: 0 0 0.75rem; color: var(--muted); font-size: 0.9rem; }
.practice-note { margin-top: 1.5rem; color: var(--muted); }

.practice-shell {
    max-width: 640px;
    margin: 0 auto;
    background: #fff;
    border-radius: 20px;
    border: 1px solid var(--border);
    padding: 1.75rem 1.5rem;
    box-shadow: 0 18px 44px rgba(15,23,42,.07);
    text-align: center;
}
.practice-setup h2 { margin: 0 0 1rem; }
.practice-field-label {
    display: block;
    margin: 1rem 0 0.5rem;
    font-weight: 700;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--muted);
}
.practice-options {
    display: flex;
    flex-wrap: wrap;
    gap: 0.55rem;
    justify-content: center;
    margin-bottom: 0.35rem;
}
.practice-opt {
    border: 2px solid var(--border);
    background: #fff;
    border-radius: 999px;
    padding: 0.55rem 1rem;
    font: inherit;
    font-weight: 700;
    cursor: pointer;
    transition: border-color .15s ease, background .15s ease, color .15s ease;
}
.practice-opt.is-active {
    border-color: var(--opt-color, var(--p-color, var(--primary)));
    background: color-mix(in srgb, var(--opt-color, var(--p-color, var(--primary))) 14%, #fff);
    color: var(--opt-color, var(--p-color, var(--primary-dark)));
}
.btn-lg { padding: 0.85rem 1.6rem; font-size: 1.05rem; margin-top: 1.25rem; }

.practice-hud {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.5rem;
    margin-bottom: 1.25rem;
}
.practice-hud > div {
    background: #F8FAFC;
    border-radius: 12px;
    padding: 0.55rem;
}
.practice-prompt {
    font-size: clamp(1.6rem, 4vw, 2.2rem);
    font-weight: 800;
    margin: 0.5rem 0 1.15rem;
    color: var(--p-color, var(--primary));
}
.practice-choices {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.65rem;
}
.practice-choice {
    border: 2px solid var(--border);
    background: #fff;
    border-radius: 14px;
    padding: 0.95rem 0.75rem;
    font: inherit;
    font-size: 1.2rem;
    font-weight: 700;
    cursor: pointer;
    transition: transform .12s ease, border-color .12s ease, background .12s ease;
}
.practice-choice:hover { transform: translateY(-2px); border-color: #93C5FD; }
.practice-choice.is-correct {
    border-color: #16A34A;
    background: #DCFCE7;
    color: #166534;
}
.practice-choice.is-wrong {
    border-color: #DC2626;
    background: #FEE2E2;
    color: #991B1B;
}
.practice-feedback {
    margin: 0.9rem 0 0;
    font-weight: 700;
}
.practice-feedback.is-ok { color: #166534; }
.practice-feedback.is-bad { color: #991B1B; }

.practice-results h2 { margin: 0 0 1rem; }
.practice-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.65rem;
    margin-bottom: 1rem;
}
.practice-stat {
    background: linear-gradient(160deg, color-mix(in srgb, var(--p-color, #22C55E) 16%, #fff), #fff);
    border-radius: 14px;
    padding: 0.9rem 0.5rem;
    border: 1px solid var(--border);
}
.practice-stat span {
    display: block;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .05em;
    color: var(--muted);
    margin-bottom: 0.25rem;
}
.practice-stat strong {
    font-size: 1.45rem;
    color: var(--p-color, var(--primary));
}
.practice-summary { color: var(--muted); margin: 0 0 1.15rem; }
.practice-end-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.65rem;
    justify-content: center;
    margin-bottom: 0.85rem;
}
.practice-app-pitch {
    margin: 0;
    font-size: 0.9rem;
    color: var(--muted);
}
.practice-more { margin-top: 2.5rem; }
.practice-more h3 { margin: 0 0 0.75rem; }

@media (max-width: 860px) {
    .calc-layout { grid-template-columns: 1fr; }
    .calc-row { grid-template-columns: 1fr; }
    .practice-choices { grid-template-columns: 1fr; }
}

/* Formula ? worksheet practice (same page) */
.formula-ws-panel {
    margin-top: 1.25rem;
    padding: 1.15rem 1.2rem;
    border-radius: 16px;
    background: linear-gradient(160deg, color-mix(in srgb, var(--f-accent, #93C5FD) 45%, #fff), #fff);
    border: 1px dashed color-mix(in srgb, var(--f-color, #2563EB) 35%, #E2E8F0);
    animation: formulaRise .35s ease;
}
.formula-ws-panel h3 {
    margin: 0 0 0.35rem;
    font-size: 1.1rem;
    color: var(--f-color, var(--primary));
}
.formula-ws-panel > p {
    margin: 0 0 0.9rem;
    color: var(--muted);
    font-size: 0.92rem;
}
.formula-grade-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: 0.55rem;
}
.formula-grade-chip {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
    padding: 0.7rem 0.75rem;
    border-radius: 12px;
    background: #fff;
    border: 2px solid var(--border);
    text-decoration: none !important;
    color: inherit;
    transition: transform .15s ease, border-color .15s ease, box-shadow .15s ease;
}
.formula-grade-chip strong {
    color: var(--g-color, var(--primary));
    font-size: 0.95rem;
}
.formula-grade-chip span {
    font-size: 0.78rem;
    color: var(--muted);
    font-weight: 600;
}
.formula-grade-chip:hover {
    transform: translateY(-2px);
    border-color: var(--g-color, #93C5FD);
    box-shadow: 0 8px 20px rgba(15,23,42,.08);
}
.formula-grade-chip.is-active {
    border-color: var(--g-color, var(--primary));
    background: color-mix(in srgb, var(--g-color, #2563EB) 10%, #fff);
}
.formula-ws-empty { margin: 0; }
.formula-ws-toolbar {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 1rem;
    align-items: flex-start;
    margin-bottom: 1.25rem;
}
.formula-ws-toolbar h2 { margin: 0 0 0.4rem; }
.formula-ws-toolbar p { margin: 0; }
.formula-ws-sheet {
    background: #fff;
    border-radius: 16px;
    padding: 1.25rem;
    border: 1px solid var(--border);
    box-shadow: 0 14px 36px rgba(15,23,42,.06);
}
@supports not (background: color-mix(in srgb, red 50%, blue)) {
    .formula-ws-panel { background: #EFF6FF; }
    .formula-grade-chip.is-active { background: #DBEAFE; }
}

/* Internal links hub (SEO) */
.internal-links {
    background: #0F172A;
    color: #CBD5E1;
    padding: 2.5rem 0 2.25rem;
    border-top: 1px solid rgba(148, 163, 184, 0.18);
}
.internal-links-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 1.75rem 1.5rem;
}
.internal-links-col h2 {
    margin: 0 0 0.85rem;
    font-size: 0.95rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: #F8FAFC;
}
.internal-links-col ul {
    list-style: none;
    margin: 0;
    padding: 0;
}
.internal-links-col li {
    margin: 0 0 0.45rem;
}
.internal-links-col a {
    color: #94A3B8;
    text-decoration: none;
    font-size: 0.88rem;
    font-weight: 500;
    line-height: 1.35;
    transition: color 0.15s ease;
}
.internal-links-col a:hover {
    color: #93C5FD;
}

@media (max-width: 960px) {
    .internal-links-grid {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 560px) {
    .internal-links-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}

@media print {
    .internal-links { display: none !important; }
}

/* Game landing pages */
.game-landing-hero {
    background:
        radial-gradient(circle at 12% 30%, color-mix(in srgb, var(--mode-color, #2563EB) 22%, transparent), transparent 45%),
        linear-gradient(135deg, #EFF6FF, #F8FAFC) !important;
}
.game-landing {
    display: grid;
    grid-template-columns: 1.4fr 0.8fr;
    gap: 1.5rem;
    align-items: start;
}
.game-landing-main {
    display: grid;
    gap: 1rem;
}
.game-info-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.25rem 1.35rem;
    box-shadow: 0 10px 28px rgba(15,23,42,.05);
}
.game-info-card h2 {
    margin: 0 0 0.65rem;
    font-size: 1.15rem;
    color: var(--primary-dark);
}
.game-info-card > p {
    margin: 0;
    color: var(--muted);
    line-height: 1.55;
}
.game-steps {
    margin: 0;
    padding-left: 1.2rem;
    color: #334155;
}
.game-steps li { margin: 0.4rem 0; }
.game-benefits {
    margin: 0;
    padding-left: 1.2rem;
    color: #334155;
}
.game-benefits li {
    margin: 0.4rem 0;
    font-weight: 600;
}
.game-play-cta { margin-top: 0.35rem; }
.game-landing-aside {
    display: grid;
    gap: 0.85rem;
}
.game-aside-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.15rem;
}
.game-aside-card h3 {
    margin: 0 0 0.5rem;
    font-size: 1.05rem;
}
.game-aside-card > p {
    margin: 0 0 0.85rem;
    color: var(--muted);
    font-size: 0.9rem;
}
.game-sign-lg {
    width: 3.5rem;
    height: 3.5rem;
    border-radius: 14px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: var(--mode-color, var(--primary));
    color: #fff;
    font-weight: 800;
    margin-bottom: 0.65rem;
}
.game-related-list {
    list-style: none;
    margin: 0;
    padding: 0;
}
.game-related-list li { margin: 0.4rem 0; }
.game-related-list a {
    color: var(--primary);
    font-weight: 600;
    text-decoration: none;
    font-size: 0.92rem;
}
.game-related-list a:hover { text-decoration: underline; }

@media (max-width: 860px) {
    .game-landing { grid-template-columns: 1fr; }
}

/* SEO / Topics / Search / FAQ */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    border: 0;
}
.header-search {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 999px;
    overflow: hidden;
    max-width: 180px;
}
.header-search input {
    border: 0;
    padding: 0.45rem 0.7rem;
    width: 100%;
    font: inherit;
    font-size: 0.85rem;
    background: transparent;
    min-width: 0;
}
.header-search button {
    border: 0;
    background: transparent;
    padding: 0.45rem 0.7rem;
    cursor: pointer;
    color: var(--primary);
    font-weight: 700;
}
.site-search-form {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-top: 1rem;
}
.site-search-form input[type="search"] {
    flex: 1;
    min-width: 200px;
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 0.75rem 1rem;
    font: inherit;
}
.site-search-form-lg input { font-size: 1.05rem; }
.search-results { display: grid; gap: 0.65rem; }
.search-result {
    display: block;
    padding: 0.95rem 1.1rem;
    border-radius: 12px;
    background: #fff;
    border: 1px solid var(--border);
    text-decoration: none !important;
    color: inherit;
}
.search-result:hover { border-color: #93C5FD; }
.search-type {
    display: inline-block;
    font-size: 0.72rem;
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: .04em;
    color: var(--primary);
    margin-bottom: 0.25rem;
}
.search-result strong { display: block; margin-bottom: 0.2rem; }
.search-result p { margin: 0; color: var(--muted); font-size: 0.9rem; }

.topic-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 1rem;
}
.topic-card {
    display: block;
    padding: 1.2rem;
    border-radius: 16px;
    background: #fff;
    border: 1px solid var(--border);
    text-decoration: none !important;
    color: inherit;
    transition: transform .15s ease, box-shadow .15s ease;
}
.topic-card:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow);
}
.topic-card h2, .topic-card h3 { margin: 0 0 0.4rem; font-size: 1.15rem; }
.topic-card p { margin: 0 0 0.75rem; color: var(--muted); font-size: 0.9rem; }

.landing-layout {
    display: grid;
    grid-template-columns: 1.4fr 0.75fr;
    gap: 1.5rem;
}
.meta-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    margin: 0.75rem 0;
}
.faq-block { margin-top: 2rem; }
.faq-block h2 { margin: 0 0 0.85rem; }
.faq-list { display: grid; gap: 0.55rem; }
.faq-item {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 0.85rem 1rem;
}
.faq-item summary {
    font-weight: 700;
    cursor: pointer;
}
.faq-item p {
    margin: 0.65rem 0 0;
    color: var(--muted);
    line-height: 1.5;
}
.related-block { margin-top: 2rem; }
.related-block h2 { margin: 0 0 0.85rem; }
.related-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 1rem;
}
.related-col h3 {
    margin: 0 0 0.45rem;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: .04em;
    color: var(--muted);
}
.related-col ul { list-style: none; margin: 0; padding: 0; }
.related-col li { margin: 0.3rem 0; }
.related-col a {
    color: var(--primary);
    font-weight: 600;
    text-decoration: none;
    font-size: 0.92rem;
}
.related-col a:hover { text-decoration: underline; }

.learn-layout {
    display: grid;
    grid-template-columns: 200px 1fr;
    gap: 1.75rem;
    align-items: start;
}
.learn-toc {
    position: sticky;
    top: 5.5rem;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 1rem;
}
.learn-toc h2 { margin: 0 0 0.55rem; font-size: 0.95rem; }
.learn-toc ol { margin: 0; padding-left: 1.1rem; }
.learn-toc a { color: var(--primary); text-decoration: none; font-size: 0.88rem; font-weight: 600; }

.ws-ready-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: 0.65rem;
    margin-bottom: 1rem;
}
.ws-ready-card {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    padding: 0.85rem;
    border-radius: 12px;
    background: #fff;
    border: 1px solid var(--border);
    text-decoration: none !important;
    color: inherit;
}
.ws-ready-card:hover { border-color: #93C5FD; }
.ws-ready-card span { color: var(--muted); font-size: 0.82rem; }

.pagination {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    margin: 1rem 0 1.5rem;
}
.pagination a {
    display: inline-flex;
    min-width: 2rem;
    height: 2rem;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    border: 1px solid var(--border);
    text-decoration: none;
    color: var(--muted);
    font-weight: 700;
    font-size: 0.88rem;
}
.pagination a.is-active {
    background: var(--primary);
    border-color: var(--primary);
    color: #fff;
}

img { max-width: 100%; height: auto; }

@media (max-width: 960px) {
    .landing-layout,
    .learn-layout { grid-template-columns: 1fr; }
    .learn-toc { position: static; }
    .header-search-desktop { display: none; }
    .header-search-mobile {
        display: flex;
        max-width: none;
        margin-top: 0.75rem;
        border-radius: 12px;
    }
}

.header-search-mobile { display: none; }

.skip-link {
    position: absolute;
    left: -9999px;
    top: 0;
    z-index: 10000;
    padding: 0.75rem 1rem;
    background: var(--primary);
    color: #fff;
    font-weight: 600;
}
.skip-link:focus {
    left: 1rem;
    top: 1rem;
}

.ad-slot {
    min-height: 90px;
    margin: 0 0 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.home-grade-grid {
    margin-top: 1.25rem;
}
.home-seo-links {
    margin-top: 1.25rem;
    font-size: 0.95rem;
    color: var(--muted, #64748B);
}
.home-seo-links a { font-weight: 600; }

.practice-seo-intro {
    max-width: 40rem;
    margin-top: 0.75rem;
    opacity: 0.9;
}

.header-download-icon {
    display: inline-flex;
    align-items: center;
}
.header-download-icon svg { display: block; }

@media (max-width: 860px) {
    .site-nav.is-open .header-search-mobile { display: flex; }
}

/* ===== Download App landing (/download-app) ===== */
.app-hero {
    position: relative;
    padding: 3.5rem 0 2.5rem;
    background:
        radial-gradient(ellipse 80% 60% at 10% 0%, rgba(37, 99, 235, 0.14), transparent 55%),
        radial-gradient(ellipse 50% 40% at 90% 20%, rgba(245, 158, 11, 0.12), transparent 50%),
        #F8FAFC;
    overflow: hidden;
}
.app-hero-inner {
    display: grid;
    grid-template-columns: 1.15fr 0.85fr;
    gap: 2.5rem;
    align-items: center;
}
.app-hero h1 {
    font-size: clamp(1.85rem, 4vw, 2.75rem);
    margin: 0.35rem 0 0.75rem;
    line-height: 1.15;
}
.app-hero-lead { max-width: 36rem; color: #475569; font-size: 1.05rem; }
.app-rating-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.45rem 0.75rem;
    margin: 1.1rem 0 1.35rem;
}
.app-stars { color: #F59E0B; letter-spacing: 0.05em; }
.app-rating-meta { color: #64748B; font-size: 0.92rem; }
.app-hero-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; }
.btn-play-store { display: inline-flex; align-items: center; gap: 0.5rem; }
.play-badge {
    display: inline-flex;
    width: 1.35rem;
    height: 1.35rem;
    border-radius: 4px;
    background: rgba(255,255,255,0.2);
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
}
.app-qr-block {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-top: 1.75rem;
    padding: 0.85rem 1rem;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 14px;
    max-width: 22rem;
}
.app-qr-block img {
    border-radius: 8px;
    flex-shrink: 0;
}
.app-qr-block p { margin: 0.2rem 0 0; font-size: 0.88rem; color: #64748B; }

.phone-frame {
    width: 240px;
    margin: 0 auto;
    border-radius: 28px;
    padding: 10px;
    background: #0F172A;
    box-shadow: 0 24px 50px rgba(15, 23, 42, 0.22);
}
.phone-frame-sm { width: 170px; border-radius: 22px; padding: 8px; }
.phone-notch {
    width: 36%;
    height: 8px;
    margin: 4px auto 10px;
    background: #334155;
    border-radius: 999px;
}
.phone-screen {
    min-height: 360px;
    border-radius: 20px;
    padding: 1.25rem 1rem;
    background: linear-gradient(165deg, var(--shot-color, #2563EB) 0%, #0F172A 120%);
    color: #fff;
}
.phone-frame-sm .phone-screen { min-height: 260px; padding: 1rem 0.85rem; }
.phone-brand { font-weight: 800; font-size: 1.15rem; margin: 0; }
.phone-tag { opacity: 0.85; margin: 0.35rem 0 1.25rem; font-size: 0.9rem; }
.phone-tiles {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
}
.phone-tiles span {
    background: rgba(255,255,255,0.14);
    border-radius: 12px;
    padding: 0.85rem 0.5rem;
    text-align: center;
    font-size: 0.8rem;
    font-weight: 600;
}
.phone-shot-title { font-weight: 700; font-size: 1.05rem; margin: 0.5rem 0 0.35rem; }
.phone-shot-hint { margin: 0; opacity: 0.85; font-size: 0.85rem; }

.app-shot-track {
    display: flex;
    gap: 1.25rem;
    overflow-x: auto;
    padding: 0.5rem 0.25rem 1.25rem;
    scroll-snap-type: x mandatory;
    -webkit-overflow-scrolling: touch;
}
.app-shot {
    flex: 0 0 auto;
    scroll-snap-align: start;
    margin: 0;
    text-align: center;
}
.app-shot figcaption {
    margin-top: 0.65rem;
    font-weight: 600;
    font-size: 0.92rem;
}

.app-feature-grid {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.75rem 1.25rem;
}
.app-feature-grid li {
    display: flex;
    align-items: flex-start;
    gap: 0.55rem;
    background: var(--surface, #fff);
    border: 1px solid var(--border);
    border-radius: 14px;
    padding: 0.9rem 1rem;
    font-weight: 600;
}
.app-feature-grid span { color: #16A34A; font-weight: 800; }

.app-why-layout {
    display: grid;
    grid-template-columns: 1.3fr 0.7fr;
    gap: 2rem;
    align-items: start;
}
.app-why-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: grid;
    gap: 0.75rem;
}
.app-why-list li {
    display: flex;
    gap: 0.6rem;
    align-items: flex-start;
    font-size: 1.02rem;
}
.app-why-list span { color: #2563EB; font-weight: 800; }
.app-why-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 18px;
    padding: 1.5rem;
    box-shadow: var(--shadow);
}

.app-video-wrap {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    border-radius: 16px;
    overflow: hidden;
    background: #0F172A;
}
.app-video-wrap iframe {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

.app-review-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1.25rem;
}
.app-review-card {
    margin: 0;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 1.35rem;
}
.app-review-card footer {
    margin-top: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
    color: #64748B;
    font-size: 0.9rem;
}

.app-stats-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 1rem;
}
.app-stat {
    text-align: center;
    padding: 1.5rem 1rem;
    background: #fff;
    border-radius: 16px;
    border: 1px solid var(--border);
}
.app-stat strong {
    display: block;
    font-size: 1.75rem;
    color: #2563EB;
}
.app-stat span { color: #64748B; font-size: 0.92rem; }

.app-related-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.75rem;
}
.app-related-card {
    display: block;
    text-align: center;
    padding: 1.1rem 1rem;
    border-radius: 14px;
    border: 1px solid var(--border);
    background: #fff;
    font-weight: 700;
    color: inherit;
    text-decoration: none;
}
.app-related-card:hover {
    border-color: #2563EB;
    color: #2563EB;
}

.app-sticky-cta {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 40;
    background: rgba(255,255,255,0.96);
    border-top: 1px solid var(--border);
    backdrop-filter: blur(8px);
    padding: 0.65rem 0;
}
.app-sticky-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}
.app-sticky-copy {
    display: flex;
    flex-direction: column;
    gap: 0.1rem;
    min-width: 0;
}
.app-sticky-copy span {
    font-size: 0.85rem;
    color: #64748B;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}
body:has(.app-sticky-cta) { padding-bottom: 4.5rem; }

@media (max-width: 900px) {
    .app-hero-inner,
    .app-why-layout { grid-template-columns: 1fr; }
    .app-hero-phone { order: -1; }
    .phone-frame { width: 200px; }
    .app-feature-grid,
    .app-review-grid,
    .app-stats-grid,
    .app-related-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 560px) {
    .app-feature-grid,
    .app-review-grid,
    .app-stats-grid,
    .app-related-grid { grid-template-columns: 1fr; }
    .app-sticky-copy span { display: none; }
}

.download-app-page { padding-bottom: 4.75rem; }
body:has(.app-sticky-cta) { padding-bottom: 0; }